In cellular networks, multicast broadcast multimedia services (MBMS) has been put to practical use as a scheme of delivering the same content as broadcast content to a plurality of users. In particular, in Long Term Evolution (LTE), an MBMS over single frequency network (MBSFN) in which base stations of a plurality of cells are mutually synchronized to deliver the same content has been standardized. Through an MBSFN, received signals from a plurality of base stations are combined so that reception quality can be improved.
Technologies have been proposed.
In an MBSFN, a plurality of base stations transmit the same data with the same radio resources. Therefore, in order to allow a long delay spread, an extended cyclic prefix (CP) of 16.7 us or 33.3 us is used in MBSFN regions of MBSFN subframes. When the extended CP of 16.7 us is used, 6 OFDM symbols are included in one slot. That is, 12 OFDM symbols are included in one subframe. On the other hand, when the extended CP of 33.3 us is used, 3 OFDM symbols are included in one slot. That is, 6 OFDM symbols are included in one subframe.
For example, Non-Patent Literature 1 discloses a technology standardized for MBMS and MBSFN.